Safe for use on every kind of wheel, the brushes in this set are densely packed with hundreds of bristles and feather-tipped for gentle agitation and effective cleaning on all kinds of road grime. These alkaline and acid resistant brushes are even great on tires. The 2" bristles are secured to heavy duty handles that won't slip out of your grip. The shorter 8.5" style brush provides close-range scrubbing of wheels and tires, and the 20" style is great for wheel wells and reaching any other awkward spaces.